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Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


My mother got me one of these for Christmas when I was a young'un.



I played it in church and then she took it away. But she gave it back to me later, she was that kind of mom.

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Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


The problem with CD changers was that you'd get one that could handle N CDs, and then as soon as you owned N+1 CDs it was just as much of a pain in the rear end as if you had just a single-disc player. If not moreso, the Pioneer changers had ittle cartridges that you'd load 6 discs into, and then insert the cartridge into the changer:



They made one model of I know of that took three of those things. 18 discs. But if you own 19 CDs, you've got to eject the cartridge, flip out one of the discs, take it out, put a new disc in, close the cartridge, plug the cartridge back in, and then play.


There are laser phonograph players, did you know. Instead of scraping a needle down the groove of your pristine, coddled vinyl, they shine a laser, just like a CD player does. I have no idea how they sound, a needle at least has the advantage that it can push aside some dust instead of reading it. They cost like $20,000 loving dollars. But a friend of mine in high school had something almost as cool. It was just a record player, with a regular old needle, but it had a tray like a CD player or even more like a laserdisc player. You'd eject the tray, load in a record, and press play. It didn't have a regular tone-arm, it had a track with a needle in it so it would always move perpendicular to the groove (the way a tone-arm swings in an arc annoys some audiophiles, I'm led to understand).

But the cool thing was it had a laser. Not to play the record, but it had an optical sensor that could use the laser to tell the difference between the songs and the spaces between the songs. So you didn't have to pick up the needle and move it to a new song, it had track-skip buttons (and FF and reverse) just like a CD player did.

Only one I ever saw.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Parallel Paraplegic posted:



Of course, barely any radiation is emitted from them at all, definitely not dangerous levels unless you sleep with it under your pillow every night for 12 years and it leaks, but you can still use them to freak out your dad.

Even if you did that, nothing. The beta from tritium decay's only 6 KeV, it can't even get through your skin, even if it could escape from the capsule it's in, which it can't. There's nothing else in the decay chain to worry about since it decays right to stable helium. And what's in the capsule is either tritium gas in a tube lined with a phosphor or tritiated water, so if the capsule leaks either the water drains away or the gas poofs off into the air.

If you broke one open and ingested it you'd get the equivalent of a couple of years of background radiation, but short of that it's no exposure at all.

So while tritium's several thousands of times more radioactive than radium, it's nowhere near as big a deal.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


If glass flowed even the tiniest bit below its transition temperature (Tg > 500 degrees C for window glass) it would be useless in many applications. Old telescopes would have by now become useless, instead of still being used for astronomy (yes, yes, there's a maximum size you can make a telescope mirror or lens out of glass before *creep* starts becoming a factor, but creep is something that solids do, not liquids, it is mechanically distinct from *flow*). The 200" mirror at Palomar's a big chunk of glass, it was correct to a fraction of a wavelength when it was installed and it still is today. If it flowed, at all, we'd have noticed.

If windows only ~100 years old are thicker at the bottom because they flowed, then how come glass objects created thousands of years ago haven't puddled, or even noticeably deformed? How come there are arrowheads and other sharp objects flaked out of obsidian by prehistoric dudes that are still sharper than a razor? Obsidian's what really good scalpels are made from, because they're sharper than any edge that steel will hold. Glass springs are used for vibration isolation in some applications, it's more *elastic* than steel.

It ain't a liquid. At least not until you heat it to Tg.

Phanatic has a new favorite as of 23:12 on Nov 1, 2012

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Jasper Tin Neck posted:

Might as well continue the glass talk with obsolete window tech:

Also depressingly obsolete:



Doesn't look like much, but that's a Pyrex beaker. Pyrex was invented by Corning, it's not obsolete, it's what lab glass is made out of, it's what the aforementioned 200" Palomar mirror is made from, it's a tough glass with a low coefficient of thermal expansion. That means heat it up, cool it down, it stays the same size. Since it doesn't change size, it means that it doesn't expand and contract differentially, which means it doesn't loving shatter when you take it off of a Bunsen burner and stick it in an ice bath.

They used to make kitchenware out of it. Said "Pyrex" right on it. It was the same stuff, borosilicate glass, you could cook in it with no problems. Some of it was, anyway, there were also standard mixing bowls and stuff made out of regular soda-lime glass that said "Pyrex" on them, but the stuff you were supposed to heat up? Probably real Pyrex.

But then something happened. Corning sold the kitchenware brand to some European outfit called World Kitchen. Now, all Pyrex kitchenware? Plain old soda-lime glass. Well, not exactly plain, it's tempered glass, which means that when it's still hot and molted the surface of the sheet is cooled down while the inner core stays hot, which basically sets up a lot of compressive stresses in the glass. So if you drop it, it's less likely to shatter. But the downside of tempered glass is that when it breaks, it breaks a lot, all over the place, and goes on breaking for a while.

So now your Pyrex casseroles will, if you take them out of a hot oven and put them down on a surface that, oh, has some water on it you didn't notice, or something else that wicks heat out of the glass really fast, it explodes into a bajillion tiny pieces. Good luck finding real Pyrex cookware anymore.

(This is what tempered soda-lime glass does when it breaks:)
https://www.youtube.com/watch?v=eqV5W76U8Qg

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Fozaldo posted:

Is there anything steampunk can't do ?

Yes.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


madlilnerd posted:

I don't like fingerprint recognition- what if someone hacked the fingerprint database and stole your fingerprint and 3D printed it onto a glove and went around committing crimes with your fingerprint left at the scene?

That's the big problem with biometrics. If your password is compromised, change your password. If your thumbprint is lifted, you can't exactly change that.

_Sneakers_ illustrates a great way to circumvent those electronic keypad locks:

https://www.youtube.com/watch?v=yp4LFuFCon0

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Kwyndig posted:

poo poo I finally remember what those were actually for. It's like the opposite of what you'd expect. A lot of old programs weren't speed limited if you had a higher clock speed than was originally intended for the program, so turbo buttons could step down or up your clock speed on your processor (usually between two speeds) so your programs wouldn't gently caress up.

Sometimes it did that. Sometimes it would turn off the processor cache, or the copro if there was one. But yeah, Turbo "on" means the computer's working normally, Turbo off means it's crippled.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


b0nes posted:

Anybody remember back in the day before Sound Blaster and dedicated cards came out a company perfected the way to get speech and cd quality audio out of a PC speaker previously which was only capable of beeps?

If by "perfected" you mean "they modulated a beep to make it sound like something other than a beep," yeah. Even at its cleverest (Like in "Space Hulk,") it still sounded a lot like modem handshaking:

http://en.wikipedia.org/wiki/File:S...lk_briefing.ogg

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


minato posted:

"CD-quality" is a bit of a stretch, but yeah, the old PC speakers were able to play a tone of a single frequency (and not much range) so by dedicating all your CPU power to changing that frequency as quickly as possible, you could play arbitrary waveforms. It never really got used in games that much since it needed so much CPU power.

See also the speech in C64's Impossible Mission: "Destwoy him, my wobots!"

That was different, though. Doing it with the PC speaker was basically pulse-width modulation. The speaker's just supposed to put out a square wave, moving from high to low at whatever frequency you tell it, there's no half-value it's supposed to be capable of delivering. But if you time the width of the pulse right, you can tell it to go back to the 'low' value before it reaches the 'high' value so you can be clever and get stuff that sounds like something other than a beep.

Being able to do digitized sample playback with the SID chip was a much neater hack. The SID was a combination of analog and digital circuits, all the inputs and controls were digital but the output was analog, and while it was only "technically" capable of outputting three voices, the output always had some level of bias on it at the point before it got fed to the amplifier.

So you could rapidly alter the gain of the amp and modulate that bias as a fourth voice channel. And yeah, it was very CPU intensive. And once manufacturing techniques got cleaned up that output bias was eliminated and this trick wouldn't really work. But it was really neat to mash the spacebar and hear "Ghostbusters!"

Here's the opening screen from "Neuromancer" as done on the AppleIIe, the C64, PC speaker, and the Amiga. It's kind of ridiculous how far ahead of its contemporaries the C64 is (not the Amiga, though, but that was a later generation altogether). The SID chip was a really impressive piece of hardware.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Pilsner posted:

I've never seen one in real life, only the Xerox Alto in pictures. I guess there's a reason it didn't stick.

First 10 seconds: https://www.youtube.com/watch?v=24FT3u-lhg4

Actually the whole video is kind of a museum of obsolete technology. And boobies. (Film geek bonus: Directed by David Fincher)

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Johnny Aztec posted:

At which point, the graphite in the pencil would flake off, float around, and short out something important, as graphite IS conductive.
So, sure the Russians did it "better" if you don't really give a poo poo about the lives or safety of your crew.

Also http://www.snopes.com/business/genius/spacepen.asp

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Monkey Fracas posted:

This is like some ridiculous concept that was too silly to put in a Fallout game or something. Who thought this was a good idea?

I suppose it can be attributed to nuclear power being all the rage those days- once an important new technology is discovered there tend to be a lot of dumb ideas that utilize it. Fortunately, they often lead to legitimately useful/non-earth-salting applications.

It would have worked wonderfully at its intended purpose, and so isn't really ridiculous: Nuke us and we send this your way, so Do Not Nuke Us. This thing would have done Mach 3 at ground level, even the shockwave of its passage would have broken things.

The reason it wasn't built wasn't because people realized it was a dumb idea, it was because ICBMs turned out to be a lot easier to develop than expected. So stuff like this, and the nuclear-powered B-36 bomber (yes, that's right, a big fuckoff airplane with a nuclear reactor in it, it was actually built and actually flown with an operating nuclear reactor on board, although at that point in the R&D the reactor was just along for the ride, not actually keeping the plane in the air), ended up being canceled because if you did want to salt the earth there were easier ways that also couldn't be defended against.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Vincent Van Goatse posted:

It wasn't the materials science that made it unworkable, actually. It was the much more mundane reason that there was no way in hell to make a nuclear-powered aircraft a viable proposition (under anything other than experimental conditions, at least, because by all accounts the X-6 would've flown just fine) because it's a goddamned flying nuclear reactor.

It might have flown just fine once. But since aircraft are weight-critical there was no way they could carry enough shielding to shield the entire reactor, all they could do was to stick a big heavy shield in between the reactor and the crew.

Which is bad for the rest of the airplane. It's bad for hydraulic fluid, which the irradiation would have turned to ooze. It would turn the tires into crumbling blocks of rubber. The metal structure of the aircraft would be neutron-activated and embrittled. And how do you service the damned thing? Answer: land, taxi over a specially-excavated pit, and jettison the reactor, and now ground crew can come and hook up a tow line and pull your airplane away from the pit of red-hot radioactive death.

There was actually a research facility down outside of Atlanta, containing a completely unshielded 10-megawatt reactor. It was mounted on a hydraulic lift, in a pit, and samples of stuff they wanted to irradiate to see what the radiation did to it would be arrayed near the pit. Raise the reactor, zap the hell out of everything nearby. They did this enough that the surrounding area received more radiation exposure than it would have received via the direct effects and the fallout from a full-scale nuclear war. Grass died, trees dropped their leaves.

The reason we stopped spending money figuring out how to get things like that to work was because we figured out how to get ICBMs to work. You can shoot down a bomber, even a nuclear-powered one, shooting down a ballistic missile coming in at Mach 25 is a difficult problem, even today. We didn't know what the easiest way to go was, so we threw money at everything; if building Pluto turned out to be easy, we'd have built fleets of nuclear-ramjet-powered death-spewing cruise missiles. If the nuclear B-36 turned out to be easy, we'd have done that.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


GWBBQ posted:


For anyone who's curious, Georgia Nuclear Aircraft Laboratory. Unfortunately, it's among the stubbiest of stub articles I've seen on Wikipedia. I've done a lot of research on the place, but it'll probably take a full day to write it up with references and I really don't know if I want to spend that much time on a Wikipedia article.

For anyone who's really curious, there's a good deal about it in this book:

http://www.amazon.com/Atomic-Awaken...r/dp/B008SLIAJ6

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Sunshine89 posted:


It had its faults, though. Piston engines can only be made so large, and the larger they are, the greater the risk engine fires pose. The B-36 carried some of the largest ever made, and due to the wing design (very thick, smooth and long to produce a lot of lift), had to be installed in a pusher configuration, which exacerbated the risk of fire.

The big problem was that the engines weren't designed for a pusher configuration.

In a normal, traction configuration, where the engines are mounted so that the props are in front of the wings, the intakes are behind the cylinders. So the incoming air has passed over the cylinders, cooling them and warming the air, before being ingested by the carburetors. But in the pusher configuration, it's the air intake that's out in front of the wing, so the carbs are ingesting cold, high-altitude air. So the carbs would slowly ice over, and as their intake got more and more restricted, the fuel/air mixture entering the cylinders would become more and more rich, and eventually there'd be so much unburned fuel leaving the cylinder that the engine exhaust would catch fire. Which is Bad.

The Wasp Major engined powered a bunch of aircraft, the engine fire issues were pretty much the result of mounting them in a pusher configuration. Conventional tractor configuration, the engine worked decently.

And, yeah, the B-36 was loving enormous. Later configurations had 10 engines, 4 jet engines in addition to the 6 piston-engine props. Here's one flying in formation with a B-52:



B-36 is larger, by about another 40' of wingspan. It's huge.


Phanatic has a new favorite as of 07:16 on May 11, 2013

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Datasmurf posted:

Episodes? As far as I remember, Napster was only for music.


Ah, Napster.

My school had a wholly inadequate internet connection, it was a single T1 line for something like 2000 students, so that's 1.5Mbps. During the week it was bad enough, but this was a school where about 90% of the student body went home on weekends, and they'd leave their computers running, with their Napster apps running, with their entire music connections shared. So network performance on the weekends went to *poo poo* as the upstream bandwidth was saturated with all these music uploads.

My three roommates were all CS majors and they'd had enough of this poo poo. There was some app my friend would run on his Mac which would give you a nice display showing the campus network topography and you could see at a glance which dorms were grabbing all the bandwidth. The network admins were uniformly pretty dull, so all the Linksys routers and switches in all the dorms still had the manufacturer default passwords. So they'd just look at see, oh, Dorm A, you're screwing it up for everybody, we're rebooting your router and dropping all your Napster connections. Oh, campus radio station, you're actually trying to do high-quality streaming audio of your crappy DJ spinning Everlast and Nickelback and Puddle of Mudd? No, sorry, that's not going to work, your router's rebooting.

Eventually the school just blocked Napster's default ports (1122 and 2255, I think?) and everyone switched to Gnutella. Remember Gnutella?

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Geoj posted:

That's loving terrible. Was this some technophobic private christian school or something?

No, it was in Wilkes-Barre PA. So culturally just as much of a backwater but with a lot more drinking and pre-marital sex.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Axeman Jim posted:


Each of 10100's engines was connected via a hydraulic clutch to a gearbox. Changing "gear" consisted of switching in more engines, 1 in first gear to 4 in top gear. So yes, you read that right, 10100 produced 1/4 of the power when starting as it did at top speed - despite the fact that you clearly need more power to overcome inertia at low speeds or when climbing hills. So to counteract this, the engines were turbocharged, with the auxiliary engine blowing the engines that were engaged, producing 4 times the turbocharging when running on one engine.


What...what the? I don't even.

So when you have one engine going, you have no more torque per engine than you do when you have all four engines going. Your maximum torque being output from the transmission is the exact same, no matter whether you have one engine coupled to the output or all four coupled to the output.

This, right here, is peak British engineering. What the gibbering gently caress.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


WebDog posted:


foam filled rubber bumper that was intended to gather air and cushion pedestrian impacts.



So pretty much the opposite of this:


They don't let you do that no more. by Phanatic, on Flickr

This was a concept car, so it's not like it made it onto the roads, but the fact that anyone ever built a car that looked like that for the real world as opposed to Deathrace 2000 is just

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Zereth posted:

I don't have a source, but I heard that the original M16 was presented as not needing to be cleaned, or possibly not needing to be cleaned very often.

This was completely false, but apparently when you hand a rifle to a soldier and tell them they don't need to clean it, they don't clean it. Surprise surprise, the guns experienced severe reliability problems!

Stoner claimed that. I don't know if anyone in the military claimed that, but the early rifles were delivered to troops without cleaning kits, so it might have developed as a rumor. After all if they didn't issue you a cleaning kit for your rifle it must not need one, right?

There were other big problems as well. The chambers weren't chrome-lined, so brass cartridge sitting in unlined chamber + wet Vietnam = corrosion. If you have a cleaning kit and engage in regular maintenance, not a big deal. But since you don't and aren't, it is. Then the DoD allowed cartridge manufacturers to go off-spec for the powder, and one of the ball powders that was used instead of stick powder specification had too much calcium carbonate in it (it's there to neutralize excess acid and make the powder more shelf-stable) and this caused fouling. Again, if you clean the weapon regularly, not a problem, but if you don't, guess what? The early magazines were also bad.

Gonna quote myself here from the history thread. The early M16s still weren't as bad as the Chauchat:



This was, doctrinally, a light machine gun, meaning that it's small enough to be carried by one guy, as opposed to a heavy machine gun that also comes with a big heavy tripod for another guy to haul around. Supposedly light enough to fire from the hip while walking in advance. Fired the French 8mm Lebel cartridge with a long-recoil action; that means that when you fire, the recoil drives both the barrel and the bolt backwards against a spring; at full retraction, the bolt is locked to the rear, and the barrel is driven forward again by the spring, lather, rinse, repeat.

So that brings us the first problem. If you look closely at that picture, you see that the barrel's actually enclosed in an outer sleeve. Fire too many rounds too quickly, and that barrel expands to the point where it wedges against the sleeve, and now you can't fire again until it cools off. Okay, maybe not such a big deal, it'd take like two full minutes of continuous fire to get that hot, and you're just not supposed to do that, you're supposed to fire in short intermittent bursts.

Bigger problem: Look at that magazine. The designer was nice enough to have wide slots cut in the side of it, so you could glance at it and see how many rounds you have left before you have to reload. Of course, since you're fighting in the trenches in Europe and you're surrounded by and covered in mud and muck and all sorts of filth, this means that all that crud's probably going to wind up inside your nice clean magazine, which means your gun just stopped working. Compounding this problem was the dirt-cheap fabrication of the magazine; they were very weak stampings, so very easy to bump the wrong way, and then end up with rounds that won't feed because there's a dent in your magazine. Okay, so just make new magazines, right? Sure, no problem, except there's this war on and we'll get around to doing that in 1918.

These problems were bad enough, but if it were just that it'd be just another forgettably bad weapon. But it took the Americans to elevate it from just a bad (albeit cheap and somewhat functional) design to an unholy disaster. When US Army troops first arrived in Europe, they didn't even have any machine guns, so they borrowed a bunch, and had about the same barely-acceptable results with the 16,000 Chauchats firing 8mm Lebel. But then the French manufacturer made up a bunch of them chambered in .30-06, which the Americans wanted for ammunition compatability with the .30-06 Springfield.

And those 18,000 guns just did not work. At all. You'd load them up and fire them and get maybe a couple of rounds out of them before they heated up enough that they'd refuse to extract the empty case and jam up. Troops who were issued the weapon would just ditch them and go looking for a new weapon to scrounge. Turns out the French screwed up the chamber measurements and built a weapon completely incapable of reliably firing .30-06, and the American inspectors at the factory just plain didn't notice, probably because they never bothered test-firing any of them. Whoops.

Eventually the Browning Automatic Rifle started being issued, but that was late enough in the war that we'd already just about won the thing so it didn't make a whole lot of difference. But it certainly didn't suck anywhere near as much rear end as the Chauchat.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


It's it's still fully-auto it's also a felony to even possess unless it was registered prior to 1986, so don't actually try to sell it to anyone. The ATF are complete killjoys.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Inspector_71 posted:

Speedpass loving rocked before there were CC readers in every pump.

It's still around

https://www.speedpass.com/

And it's definitely not an obsolete technology, it's one of the first consumer-level examples of RFID tags and those things are everywhere.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Wanamingo posted:

Okay, so for any aviation goons, how plausible is this? It seems like such a magnificently stupid idea that I'm really curious about whether or not it's even vaguely possible that it would ever come even remotely close to working.

Ramming wasn't uncommon during WWII. I don't mean kamikaze attacks, I mean the idea of ramming another plane to bring it down while you survive. The Luftwaffe equipped a squadron late in the war for that specific purpose.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Inspector_71 posted:

It seems kind of redundant nowadays. I guess it's handy for parents of teenagers who need to use the car but don't have their own debit/credit card?

The point is that it's just hanging off your keychain, you just wave it in front of the pump and it's tied to your card. You don't need to go into your purse or pants, grab your wallet, extract your card, swipe it, take the card out, curse, turn it around, swipe it the correct way, maybe punch in your zip code, and put your card away. Yes, all that's a decidedly first-world problem, but convenience sells.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


longview posted:

As mentioned, they are still in use for deep space probes -- and are the only reason we can still talk to the Voyager probes, -- this is a problem, since should the rocket launching the probes need to be terminated, it would spray fairly poisonous and radioactive substances (remember: lower half-life = more nuclear energy) over a pretty wide area. Hopefully the area would be large enough that individual casualties are not an issue, but the environmental concerns are huge with launching RTGs.

Not really, no.

Lower half-life means it's less radioactive, not more. Uranium-238 has a half-life of 4.5 billion years. They use it as counterweights for control surfaces on aircraft because it's nice and dense. Airplane crashes and burns up and it's a complete non-issue. Because the half-life is 4.5 *billion* years.

For a radiothermal generator on a space probe, you use a *shorter* half-life, because you need it to generate enough heat as it decays to produce a useful voltage across a thermocouple. So we typically use plutonium-238, with a half-life of about 90 years. A number of RTGs have reentered the atmosphere, and not a single one of these have caused any damage at all. Apollo 13's is sitting on the ocean bottom, there's been no measurable increase in radiation in the area. Several early and/or Soviet RTGs burned up on re-entry, increasing the background radiation of the earth by an utterly insignificant amount.

There was a big oops incident with a Soviet recon satellite which broke up and reentered over Canada, maybe that's what you're thinking of. But that wasn't an RTG, it was a nuclear reactor with 50 kilograms of U235 and a few months' operation of fission fragments. That scattered over 50,000 square miles of Canada and was a mess to clean up, but RTGs aren't fission reactors, and are specifically designed to survive reentry intact.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Geoj posted:

More disturbingly, there are a fair number (~30) of these floating around in high orbit. Soviet RORSATs were all powered by liquid metal cooled reactors, which upon reaching the end of their useful lifespans were ejected into a higher orbit that will eventually decay and re-enter the atmosphere.

900 kilometer orbit takes a really long time to decay, though, this isn't Skylab we're talking about. I mean, hundreds of years is a good order of magnitude estimate, by that time most of the fission fragments won't be a concern. The worrying ones are the ones that didn't make it to that parking orbit.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Prenton posted:

Ah, that reminds me.

Handheld joysticks


As opposed to arcade cabinet ones? Did everyone else stick these to the table or something?



The Atari ones also worked great with the C64. I remember taking typing class in middle school, you could also play games on the Apple IIs and I *hated* the analog joysticks, they were just such poo poo compared to the digital Atari ones.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


ZALGO! posted:

You see weird things like buttons above the joystick, buttons on the side of the controller, telephone-style keypads, etc.

Or all of those together. I had one of these:



Can't see them, but it had two buttons on each side of the controller. And I still don't know what the number pad was for.

But there was a track-and-field game for the C64, one of the sort where you had to flail the joystick left and right in order to run, and if you held down two of the number pad buttons and one of the side buttons you'd turn into the goddamned Flash and just win every race.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


muike posted:

What's the highest G you've pulled?



This many. Driving home at night, wrecked car in my (left) lane, stopped askew up against the Jersey barrier. That'll get your adrenaline going.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Trebek posted:

I think the problem with this concept is if it malfunctions you are completely hosed. At least with the current mechanical doors you can get in and out of your car even if your battery fails.

And the side-impact crash ratings would be abysmal.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


SomeJazzyRat posted:

If I remember that was specifically 'cause it was found in the UK. So it makes a little bit more sense due to their stricter gun laws.

Here's one that happened here.

Guy's living in Colorado. He buys three handguns, legally, has a background check and everything. He moves back home to New Jersey so he can live closer to his son, and before he moves he calls up the NJ police to find out how he can transport them legally. He has the guns locked in his trunk, unloaded, not accessible from inside the vehicle, and is transporting them from one residence to another, which is *entirely legal*.

Stops by his mom's house to pick up a few belongings, and she notices that he's upset about his relationship with his ex-wife. He leaves and starts driving to his new place in Hoboken. Mom gets briefly worried enough about him to call 911, worried that he might be suicidally depressed, and then things better of it and hangs up before the call goes through. The police show up at her place anyway, and talk to her, she tells them why she called, they call him up on his cell phone and ask him to turn around and head back to his mother's place, and he does. When they show up, they search his car and arrest him for illegal possession of handguns.

Again, there is a clear exemption in NJ law for transporting your guns between residences. But the judge didn't even allow him to argue that before the jury. The jury, during the trial, asked three times if there were exceptions to the law, the judge would not inform them as to whether there were or weren't. The judge did not allow him to even mention the fact that he called the cops to ask them how he could legally transport his guns within New Jersey. So the jury convicted him and sentenced him to seven years. Chris Christie commuted the guy's sentence, and the judge is no longer on the bench (not because of this, but because of a different case where he dismissed animal cruelty charges against a cop who stuck his dick in the mouths of five cows because he ruled there was no way of knowing that the cows had in fact been "tormented" by his actions), but a guy who did things legally, reached out to the cops to make sure he was doing things legally, and only drew the cops' attention because his mother was briefly worried about him and wanted to make sure he was okay, still had to go through legal hell and still has a conviction on his record; commutation is not the same thing as a pardon.

Do not listen to Captain Postal. Do not call the cops and say "Hey, what should I do with this machine gun I found in the attic?" The legal system is capable of being Kafkaesque enough that you don't want to get within a mile of it, even before you get guns involved. The BATF at one point issued a ruling that copper wool scouring pads are, legally, regulated as firearms and subject to a $200 transfer tax, and at another point issued a ruling that a 14" length of shoestring is a machine-gun. Several years ago a small library in Massachusetts discovered that, in its attic, a machine gun that Sgt. York, Sgt. Alvin motherfucking York, captured in the action he was the Medal of Honor for. That's a priceless historical find, and ATF wanted to destroy it, because (a) it had never been registered and (b)it could not now be registered and therefore there was no legal way to possess it. So getting your heirloom destroyed is the *best possible outcome* of calling the cops.

http://articles.philly.com/2010-11-...laws-legal-team
http://www.itemlive.com/news/nahant...5133dd7e40.html

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Pitch posted:

That's because he had been "moving" for months, and left the guns in his car the entire time. That's not kosher.

I'm not interested in turning this into a DND subforum, but that is the sort of thing that is entirely a matter of fact to be decided by the jury, not a matter of law to be decided by a judge.

But I'll go into some detail on the gun itself, since it's neat, and obsolete/failed as hell. Here's what it would look like all cleaned up:



Lockmat mentioned that he heard they were supposed to be used in planes and that's why the magazine has those cutaways, but unfortunately that's not true and doesn't let the designer off the hook. They *were* used in that role, but the original intent of the R&D program was for a light, aircooled machinegun that could easily be carried by a single person, enabling him to advance during assaults with the weapon; heavier tripod-mounted guns aren't suited for that.

The gun was, even at best, something of a piece of poo poo. One of the companies that manufactured them, which built auto parts before the war, consistently misaligned the sights. And even if you did have corrected sights, the bipod was very loose, so it was really difficult to keep on target and very fatiguing to fire.

If you could get it to fire. Even before we get to the magazine, this gun operates off the long-recoil system, which means that the the barrel recoils along with the bolt, being driven back against a spring. At the rearward limit of travel, the bolt locks to the rear, and the spring drives the barrel forward again. That means the barrel is moving back and forth within that outer, perforated aluminum sleeve. Fire too many rounds too fast, and the barrel would expand too much and lock itself in place within that sleeve until it cooled off. Okay, you're not really supposed to do that, you're just supposed to fire it in short bursts and not cut loose for two minutes at a time. So this didn't cause most of the stoppages it was plagued with.

And yeah, most of them were the fault of the magazines. In addition to the problem of dirt and muck getting in through the holes, they were just really cheap, stamped metal parts, and it was the easiest thing in the world to bang one against something and deform it enough for it to stop feeding, even if you kept it immaculately clean. The solution was to manufacture new magazines without those problems, but hey there's this war on and eventually they got around to doing that in 1918.

But even with all that, it would probably just be another forgettable lovely gun, of which there have been a lot. It took the involvement of the USA to elevate this to an unholy disaster of a weapon. The US troops showed up in Europe without any light machine guns, so they borrowed a bunch of Chauchats and had the same mediocre-at-best results. But they also wanted to buy new ones, but chambered for the .30-06 cartridge the American military used in just about everything. So a French manufacturer dutifully churned out 18,000 of them.

And those 18,000 guns, every last one of them, just did not work. At all. The French manufacturer screwed up the chamber dimensions, and the American inspectors at the factory didn't notice, so you'd get a couple or even a few rounds out of the gun and then it would heat up a bit and then it would completely fail to extract the empty case and you'd be left with a metal club. US troops who were issued the things would promptly lose them and scrounge a weapon that they could actually fire. Eventually they were abandoned in exchange for the Browning Automatic Rifle, which the French took one look at and said "We'll take 15,000 of them!" But that was late in the war, and by the time barely 10,000 BARs had been produced there was the Armistice. But *that* gun was still being produced by the tens of thousands during the Korean War, and was still in use during Vietnam. So that one might be obsolete, but it wasn't a failure.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Lord Booga posted:

There's a reason that there is a famous old joke - "If Commodore bought KFC, they would rename it Warm Dead Bird" - I loved my Amigas (they were reasonably popular here in NZ) (and have emulators for when I get that nostalgic urge), but Commodore was terrible at marketing.


Get this poo poo. At one point, Sun Microsystems went to Commodore and said "We really like that there Amiga 3000UX machine you have, the one with System V ported to it. We'd like to buy a license to be an OEM manufacturer for those and sell them as a low-end alternative to our high-end workstations."

Commodore quoted them a gently caress-right-off license price so Sun hosed right off. Instead, Commodore decided to produce this:



Effectively slitting its own wrists.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


eddiewalker posted:

I want to meet the guy trying to get homemade batteries on a plane.



Microcline posted:

Batteries generally consist of two highly reactive materials with a large amount of potential energy. They pretty much are explosives.

Except that the energy density of any chemical battery is total and complete poo poo when compared to the feeblest of high explosives.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Sham bam bamina! posted:

The worst thing is that digital synthesizers were absolute poo poo until the '90s but managed to displace the older keyboards almost overnight because they were "cutting-edge". The '80s were a real dark age for popular musical aesthetics.

Yeah, all these albums sucked:

http://www.slicingupeyeballs.com/20...ums-of-the-80s/

The synths were absolute poo poo:

https://www.youtube.com/watch?v=Zi_XLOBDo_Y

Phanatic has a new favorite as of 17:22 on Jan 6, 2014

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Ron Burgundy posted:

Nitrate fires can be extinguished with carbon tetrachloride, but that's another can of worms entirely

When I was a kid I was in a summer camp that had a few cases of these on the shelf in a storage room:



Maybe not this exact brand, but same thing: fire grenades. You'd throw them at a fire, they'd break, and they were full of carbon tetrachloride.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


Shugojin posted:

I remember reading the full hazards sheet on the big jug of carbon tetrachloride I filled a small vial from for a Raman scattering experiment (it actually has very good Raman lines) and one of the things on it was "may cause permanent genetic damage".

Has Ignition! been brought up in this thread yet? Old out-of-print (PDFs are easy to find, though) book by a former rocket scientist specializing in storable liquid fuels for various applications, most famous for its great description of a chemical spill of chlorine trifluoride:

quote:

It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water with which it reacts explosively. It can be kept in some of the ordinary structural metals steel, copper, aluminum, etc. because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminum keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes.

Ended up not being used as a rocket fuel in any production system because of the inherent dangers in storing and transporting it. Something that can set things like concrete, gravel, and steel on fire, a fire that can't be extinguished with water because it will burn the water, isn't something that navy captains want on their ships, for instance.

But the single most terrifying thing in that book is this little bit:

quote:

All sorts of efforts were being made, during the late 50's, to increase propellant densities, and I was responsible (not purposely, but from being taken seriously when I didn't expect to be) for one of the strangest. Phil Pomerantz, of BuWeps, wanted me to try dimethyl mercury, Hg(CH3)2, as a fuel. I suggested that it might be somewhat toxic and a bit dangerous to synthesize and handle, but he assured me that it was (a) very easy to put together, and (b) as harmless as mother's milk. I was dubious, but told him that I'd see what I could do.

I looked the stuff up, and discovered that, indeed, the synthesis was easy, but that it was extremely toxic, and a long way from harmless. As I had suffered from mercury poisoning on two previous occasions and didn't care to take a chance on doing it again, I thought that it would be an excellent idea to have somebody else make the compound for me. So I phoned Rochester, and asked my contact man at Eastman Kodak if they would make a hundred pounds of dimethyl mercury and ship it to NARTS. I heard a horrified gasp, and then a tightly controlled voice (I could hear the grinding of teeth beneath the words) informed me that if they were silly enough to synthesize that much dimethyl mercury, they would, in the process fog every square inch of photographic film in Rochester, and that, thank you just the same, Eastman was not interested.

Someone actually considered using as a rocket propellant a substance that's so toxic it's lethal if you get a drop of it on your hand, even if you're wearing lab gloves. Deciding that this was too dangerous, they used plain old inorganic, elemental mercury. They were going to fire this rocket in the middle of New Jersey, and built this big scrubber to collect the mercury in the exhaust before it made it out into the atmosphere, but then the research center was shut down by the Navy, which just test-fired the thing out in the middle of a desert somewhere and didn't bother with the scrubber.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


DicktheCat posted:

I'm vaguely surprised that the US military didn't attempt to weaponize that chlorine trifluoride stuff.



...... or maybe they did.

It would be a chemical weapon that paled in comparison to actual chemical weapons that are far easier and safer to store and transport. No reason to weaponize it at all. The Germans produced a small amount for that purpose but never used it for the same reason they didn't use their other chemical weapons.

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Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.


One of the early ways of doing color photography used black and white film, but color filters. Others did it before him, but a Russian named Sergey Prokudin-Gorsky is probably the most famous practitioner.

The way this worked is that you'd take three separate exposures of the subject, one through a red filter, one through a green filter, and one through a blue filter. Then the three developed plates could be precisely aligned, and you could either project light through a red filter, a green filter, and a blue filter, and then through the prints to yield a vibrant color projection, or use them to generate color prints with CMY inks. To avoid having to actually load the camera, take a shot, and then repeat that two more times while keeping everything aligned, there were special cameras for this that'd split the incoming light and send it to all three plates at the same time.

The results were pretty spectacular. This one's from 1911:





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